The eastern section of the trough has been named the Gonâve Microplate.

At its western end, the Gonâve Microplate is bounded by the mid-Cayman spreading centre.

The island of Jamaica lies on the boundary between the Caribbean Plate and the Gonâve Microplate.

This observation is consistent with the eventual accretion of the Gonâve Microplate to the North American Plate.

The presence of a separate Gonâve Microplate was first suggested by the analysis of sidescan sonar results from the Cayman Trough.

The overall four cm per year displacement along this boundary is split nearly equally between two major dextral (right lateral) strike-slip zones either side of the Gonâve Microplate.

The parallel Septentrional and Enriquillo-Plantain Garden faults, which run through the island of Hispaniola and bound the Gonâve Microplate, are also a part of the boundary.

This has been confirmed by GPS measurements, which show that the overall displacement between the two main plates is split almost equally between the transform fault zones that bound the Gonâve microplate.

The Gonâve Microplate began to form in the Early Eocene after the northern part of the leading edge of the Caribbean Plate (present day Cuba) collided with the Bahamas platform.

The Gonâve Microplate is an approximately 1,100 km long strip, consisting mainly of oceanic crust of the Cayman Trough but including island arc material at its eastern end on the western part of Hispaniola.